Problem: $\dfrac{3}{5} \div \dfrac{4}{7} = {?}$
Explanation: Dividing by a fraction is the same as multiplying by the reciprocal of the fraction. The reciprocal of $\dfrac{4}{7}$ is $\dfrac{7}{4}$ Therefore: $ \dfrac{3}{5} \div \dfrac{4}{7} = \dfrac{3}{5} \times \dfrac{7}{4} $ $ \phantom{\dfrac{3}{5} \times \dfrac{7}{4}} = \dfrac{3 \times 7}{5 \times 4} $ $ \phantom{\dfrac{3}{5} \times \dfrac{7}{4}} = \dfrac{21}{20} $